The present invention relates to novel anticancer agents, their stereoisomers, their polymorphs, their pharmaceutically acceptable salts, and their pharmaceutically acceptable solvates. The present invention more particularly relates to novel derivatives of andrographolide, their stereoisomers, their polymorphs, their pharmaceutically acceptable salts, and their pharmaceutically acceptable solvates. The novel derivatives of andrographolide have the general formula (I), 
where R1 represents hydrogen, halogen, thio, or substituted or unsubstituted alkyl, alkylthio, heteroarylthio, acylthio, aralkylthio, arylthio, alkylseleno, acylseleno, aralkylseleno, arylseleno, NRaRb where Ra, and Rb may be same or different and independently represent hydrogen, substituted or unsubstituted alkyl, aryl, acyl, aralkyl, heteroaryl, haloalkyl, or haloacyl or Ra and Rb together with the nitrogen atom to which they are attached may form substituted or unsubstituted 5 or 6 membered cyclic ring system containing carbon atoms, at least one nitrogen atom and optionally one or more hetero atoms selected from oxygen, sulfur or nitrogen, the cyclic ring system may contain one or two double bonds or it may be aromatic or R1 may represent OR6 where R6 represents hydrogen or substituted or unsubstituted groups selected from alkyl, aryl, aralkyl, alkenoyl, alkanoyl, aroyl, heteroaroyl, aralkenoyl, aralkanoyl, sulfonyl groups or a group xe2x80x94(CO)xe2x80x94NHxe2x80x94R7 where R7 represents substituted or unsubstituted groups selected from alkyl, aryl, or aralkyl; R2 and R3 may be same or different and independently represent hydrogen or substituted or unsubstituted groups selected from alkyl, aryl, heteroaryl, aralkyl, heteroaralkyl, alkanoyl, alkenoyl, aroyl, heteroaroyl, aralkenoyl, aralkanoyl, sulfonyl group or a group xe2x80x94(CO)xe2x80x94Wxe2x80x94R8 where W represents O, S or NR9, wherein R9 represents hydrogen or (C1-C6)alkyl group, R8 represents substituted or unsubstituted groups selected from alkyl, aryl, aralkyl or aroyl or OR2 and OR3 together form a substituted or unsubstituted 6 or 7 membered cyclic structure containing carbon and oxygen atoms; and R4 and R5 together represents xe2x95x90CH2 or an epoxide group.
The andrographolide derivatives represented by general formula (I) defined above of the present invention and general formulas (IX), (X) and (XI) as defined below are useful for treating cancer and other proliferative diseases including but not limited to herpes simplex virus types I and II (HSV I and HSV II) and human immunodeficiency (HIV). The compounds of the present invention are also useful in the treatment of psoriasis, restonosis, atherosclerosis and other cardiovascular disorders. The compounds of the present invention are also useful as antiviral, antimalarial, antibacterial, hepatoprotective, immunomodulating agents and for treatment of metabolic disorders. The anticancer activity exhibited may be through cytotoxic activity, antiproliferation, cell cycle kinase inhibition or may be through cell differentiation.
The compounds of this invention are also useful for the treatment and/or prophylaxis of insulin resistance (type II diabetes), leptin resistance, impaired glucose tolerance, dyslipidemia, body weight reduction, disorders related to syndrome X such as hypertension, obesity, insulin resistance, coronary heart disease and other cardiovascular disorders.
The present invention also relates to pharmaceutical compositions containing compounds of general formula (I), formula (IX), formula (X), or formula (XI), or their stereoisomers, their polymorphs, their salts, or their solvates or mixtures thereof.
The present invention also relates to a process for the preparation of the compounds of general formula (I), formula (IX), formula (X), and formula (XI), and their stereoisomers, their polymorphs, their pharmaceutically acceptable salts, and their pharmaceutically acceptable solvates.
The plant andrographis paniculata is extensively used in medicine as a bitter tonic, febrifuge and in bowel complaints (Glossary of Indian Medicinal Plants., Ed. R. N. Chopra, S. L. Nayar, I. C. Chopra, p18, 1996; The useful plants of India, Ed. By S. B. Ambasta, p39, 1992). The plant is useful in the treatment of bacterial infections (Int. J. Crude Drug Res. 1990, 28(4), p273-283; Drugs of the Future. 1990, 15(8) p809-816). It is reported to possess antimalarial (Int. J. Pharmacognosy, 1992, 30(4), p263-274; J. Ethnopharmocol., 1999, 64(3), p249-254) and immunostimulant activity (J. Nat. Prod., 1993, 56(7), p995-999). The plant has also been shown to be antithrombotic (Chinese Medical Journal 1991, 104(9), p770-775) and inhibit stenosis and restenosis after angioplasty in the rat (Chinese Medical Journal, 1994, 107(6), p464-470). It is also known that the plant extract and its constituents exhibit promising hepatoprotective activity (Planta Medica, 1987, 53(2), p135-140). Significant attention has been paid by several research groups on A. paniculata in recent years due to its cytotoxic, antitumorogenic, cell differentiation inducing activities and anti-HIV activities.
Andrographolide having the formula (II), 
the major constituent of the plant A. paniculata was first isolated by Gorter (Rec. trav. chim., 1911, 30, p151-160). 
The extracts of the dried plant, which contains compounds of formula (III), have been assayed for the ability to decrease expression and phosphorylation of p34cdc2 kinase, cyclin B and c-Mos for treating or preventing pathogenecity of diseases such as AIDS, Alzheimer""s disease and hepatitis (WO 96/17605).
Cell cycle kinases are naturally occurring enzymes involved in regulation of the cell cycle (Progress in Cell Cycle Research, 1995, 1, p351-363). Typical enzymes include the cyclin-dependent kinases (cdk) cdk1, cdk2, cdk4, cdk5, cdk6 and wee-1 kinase. Increased activity or temporarily abnormal activation of these kinases has been shown to result in development of tumors and other proliferative disorders such as restenosis. Compounds that inhibit cdks, either by blocking the interaction between a cyclin and its kinase partner or by binding to and inactivating the kinase, cause inhibition of cell proliferation and are thus useful for treating tumors or other abnormally proliferating cells.
The extract of A. paniculata was found to show significant cytotoxic activity against KB and P388 cells. Interestingly, Andrographolide of the formula II, has been shown for the first time to have potent cytotoxic activity against KB as well as P388 lymphocytic leukemia, where as 14-deoxy-11,12-didehydroandrographolide and neoandrographolide having the formulae IV and V 
where R represents xcex2-D-glucose moiety, have shown no cytotoxic activity in tumor cell lines (J. Sci. Soc. Thailand, 1992, 18, p187-194).
The methanolic extract of the aerial parts of A. paniculata Nees showed potent cell differentiation inducing activity on mouse myeloid leukemia (M1) cells (Chem. Pharm. Bull. 1994, 42(6) 1216-1225).
Japanese patent application JP 63-88124, discloses a mixture of at least two compounds of formula VIa, VIb, 
where R1, R2, R3, R4 and R5 represent hydrogen or lower alkanoyl group and discloses their activity as antitumorogenic agents.
DASM (dehydroandrographolide succinic acid monoester) prepared from andrographolide of the formula II is found to be inhibiting HIV virus and nontoxic to the H9 cell at the concentrations of 50-200 xcexcg/ml and was inhibitory to HIV-1(IIIB) at the minimal concentration of 1.6-3.1 xcexcg/ml (Proc. Soc. Exp. Biol. Med., 1991, 197, p59-66).
The plant Andrographis paniculata is also reported to inhibit proprotein convertases-1, -7 and furin possibly by suppressing the proteolytic cleavage of envelops glycoprotein gp 160 of HIV, which is known to be PC-mediated, particularly by furin and PC (Biochem. J., 1999, 338, 107-113)
In International patent application WO 91/01742, compositions containing one or more ingredients obtained from the plants Valeariana officinalis and/or A. paniculata were disclosed to have antiviral, antineoplastic, antibacterial and immunomodulatory activity.
Although several novel andrographolide derivatives have been prepared, screened and reported in the above said prior-art literature for their anticancer activity, they are not showing interesting activity.
With an objective of preparing novel andrographolide derivatives useful for treating cancer, diseases and infections caused by HSV and HIV, psoriasis, restenosis, atherosclerosis, cardiovascular disorders, also useful as antiviral, antimalarial, antibacterial, hepatoprotective, immunomodulating agents and for treatment of metabolic disorders, which are potent at lower doses and having better efficacy with lower toxicity, we focussed our research efforts in preparing the novel andrographolide derivatives of the formula (I) as defined above.
The main objective of the present invention is, therefore, to provide novel andrographolide derivatives of the formula (J) as defined above, and formulas (IX), (X) and (XI) as defined below, their stereoisomers, their polymorphs, their pharmaceutically acceptable salts, their pharmaceutically acceptable solvates and compositions containing them or their mixtures.
Another objective of the present invention is to provide pharmaceutical compositions containing compounds of the general formula (I), formula (IX), formula (X), formula (XI), their stereoisomers, their polymorphs, their pharmaceutically acceptable salts, or their pharmaceutically acceptable solvates or their mixtures in combination with suitable carriers, solvents, diluents and other media normally employed in preparing such compositions.
Still another objective of the present invention is to provide pharmaceutical compositions containing compounds of formula (I), formula (IX), formula (X), formula (XI), their stereoisomers, their polymorphs, their pharmaceutically acceptable salts, or their pharmaceutically acceptable solvates, their mixtures in combination with one or more pharmaceutically acceptable active compounds with suitable carriers, solvents, diluents and other media normally employed in preparing such compositions.
Still another objective of the present invention is to provide a process for the preparation of novel andrographolide derivatives of the formula (I), formula (IX), formula (X), and formula (XI), their stereoisomers, their polymorphs, their pharmaceutically acceptable salts, and their pharmaceutically acceptable solvates and pharmaceutical compositions containing them or their mixtures having enhanced activity, no toxic effect or reduced toxic effect.
Accordingly, the novel derivatives of andrographolide of the present invention have the general formula (I) 
where R1 represents hydrogen, halogen, thio, or substituted or unsubstituted alkyl alkylthio, heteroarylthio, acylthio, aralkylthio, arylthio, alkylseleno, acylseleno, aralkylseleno, arylseleno, NRaRb where Ra, and Rb may be same or different and independently represent hydrogen, substituted or unsubstituted alkyl, aryl, acyl, aralkyl, heteroaryl, haloalkyl, or haloacyl or Ra and Rb together with the nitrogen atom to which they are attached may form substituted or unsubstituted 5 or 6 membered cyclic ring system containing carbon atoms, at least one nitrogen atom and optionally one or more hetero atoms selected from oxygen, sulfur or nitrogen, the cyclic ring system may contain one or two double bonds or it may be aromatic or R1 may represent OR6 where R6 represents hydrogen or substituted or unsubstituted groups selected from alkyl, aryl, aralkyl, alkenoyl, alkanoyl, aroyl, heteroaroyl, aralkenoyl, aralkanoyl, sulfonyl groups or a group xe2x80x94(CO)xe2x80x94NHxe2x80x94R7 where R7 represents substituted or unsubstituted groups selected from alkyl, aryl, or aralkyl; R2 and R3 may be same or different and independently represent hydrogen or substituted or unsubstituted groups selected from alkyl, aryl, or heteroaryl, aralkyl, heteroaralkyl, alkanoyl, alkenoyl, aroyl, heteroaroyl, aralkenoyl, aralkanoyl, sulfonyl group or a group xe2x80x94(CO)xe2x80x94Wxe2x80x94R8 where W represents O, S or NR9, wherein R9 represents hydrogen or (C1-C6)alkyl group, R8 represents substituted or unsubstituted groups selected from alkyl, aryl, aralkyl or aroyl or OR2 and OR3 together form a substituted or unsubstituted 6 or 7 membered cyclic structure containing carbon and oxygen atoms; and R4 and R5 together represents xe2x95x90CH2 or an epoxide group; their stereoisomers, their polymorphs, their pharmaceutically acceptable salts and their pharmaceutically acceptable solvates.
Suitable groups represented by R1 may be selected from hydrogen, thio, halogen such as fluorine, chlorine or bromine and the like; linear or branched (C1-C8) alkyl group such as methyl, ethyl, n-propyl, iso-propyl and the like; the alkyl group may be substituted; (C1-C8)alkylthio group such as methylthio, ethylthio, propylthio and the like, the alkylthio group may be substituted; heteroarylthio group such as pyridylthio, furylthio, thiophenylthio, benzothiazolethio, purinethio, benzimidazolethio, pyrimidinethio and the like, the heteroarylthio group may be substituted; acylthio group such as acetylthio, propanoylthio, butanoylthio and the like, the acylthio group may be substituted; aralkylthio group such as benzylthio, phenylethylthio, phenylpropylthio and the like, the aralkylthio group may be substituted; arylthio group such as phenylthio, napthylthio and the like, the arylthio group may be substituted; (C1-C8)alkylseleno such as methylseleno, ethylseleno, propylseleno, iso-propylseleno and the like, the alkylseleno group may be substituted; acylseleno such as acylamino group such as acetylseleno, propionylseleno and the like, the acylseleno group may be substituted; aralkylseleno such as benzylseleno, phenylethylseleno, phenylpropylseleno and the like, the aralkylseleno group may be substituted; arylseleno such as phenylseleno, napthylseleno and the like, the aralkylseleno group may be substituted; NRaRb or OR6.
Suitable groups represented by Ra and Rb include hydrogen, substituted or unsubstituted, linear or branched (C1-C8) alkyl group such as methyl, ethyl, n-propyl, iso-propyl and the like; aryl group such as phenyl, naphthyl and the like, the aryl group may be substituted; acyl group such as acetyl, propionyl and the like, the acyl group may be substituted; aralkyl such as benzyl, phenethyl and the like, the aralkyl group may be substituted; heteroaryl group such as pyridyl, furyl, thiophenyl, benzothiazoyl, purinyl, benzimidazoyl, pyrimidinyl, tetrazolyl and the like, the heteroaryl group may be substituted; halo(C1-C8)alkyl such as chloromethyl, bromoethyl and the like; haloacyl such as chloroacetyl and the like.
The cyclic ring system formed by Ra and Rb together with the nitrogen atoms may be selected from uracil, substituted uracil, imidazole, triazole, tetrazole, morpholine, piperazine, pyrazine, pyrimidinone, cytosine, pyrrolidine and the like.
Suitable substituents on the cyclic ring system formed by Ra and Rb together with nitrogen atoms may be selected from hydrogen, hydroxy, halogen atoms such as fluorine, chlorine, bromine and the like; linear or branched (C1-C8) alkyl group such as methyl, ethyl, n-propyl, iso-propyl and the like; (C2-C6)alkenyl group such as ethenyl, propenyl, butenyl and the like; (C2-C6)alkylenyl such as acetylenyl, propylenyl, butylenyl and the like; amino, nitro, oxo, thio, and imino groups.
Suitable groups represented by R2 and R3 include hydrogen, substituted or unsubstituted, linear or branched (C1-C8) alkyl group such as methyl, ethyl, n-propyl, iso-propyl and the like; aryl group such as phenyl, naphthyl and the like, the aryl group may be substituted; heteroaryl group such as pyridyl, furyl, thiophenyl and the like, the heteroaryl group may be substituted; aralkyl such as benzyl, phenethyl and the like, the aralkyl group may be substituted; heteroaralkyl group such as pyridylmethyl, pyridylethyl, furanmethyl, furanethyl and the like, the heteroaralkyl group may be substituted; (C2-C8) alkanoyl group such as ethanoyl, propanoyl, butanoyl and the like, the (C2-C8) alkanoyl group may be substituted; (C3-C8) alkenoyl group such as propenoyl, butenoyl, pentenoyl and the like, (C3-C8) alkenoyl group may be substituted; aroyl group such as benzoyl and the like, the aroyl group may be substituted; heteroaroyl group such as pyridyl carbonyl, furyl carbonyl and the like; the heteroaroyl group may be substituted; aralkenoyl group such as phenylpropenoyl, phenylbutenoyl, phenylpentenoyl and the like, the aralkenoyl group may be substituted; aralkanoyl group such as phenylpropanoyl, phenylbutanoyl, phenylpentanoyl and the like, the aralkanoyl group may be substituted; sulfonyl group such as methanesulfonyl, benzenesulfonyl, p-toluenesulfonyl and the like, the sulfonyl group may be substituted.
Suitable cyclic structures formed by OR2 and OR3 may be selected from xe2x80x94Oxe2x80x94(CR10R11)mxe2x80x94Oxe2x80x94 where R10 and R11 may be same or different and independently represent hydrogen, or unsubstituted or substituted groups selected from (C1-C6) alkyl such as methyl, ethyl, n-propyl and the like; aryl group such as phenyl, naphthyl and the like, the aryl group may be substituted; heteroaryl group such as pyridyl, furyl, thiophenyl, pyrrolyl and the like; the heteroaryl group may be substituted or R10 and R11 together represent Cxe2x95x90O; and m represents an integer 1 or 2. The substituents on R9 and R10 include hydroxy, halogen such as fluorine, chlorine, bromine and the like; nitro, cyano or amino groups.
Suitable groups represented by R6 may be selected from hydrogen, linear or branched (C1-C8) alkyl group such as methyl, ethyl, n-propyl, iso-propyl and the like, the (C1-C8)alkyl group may be substituted; aryl group such as phenyl, naphthyl and the like, the aryl group may be substituted; aralkyl such as benzyl, phenethyl and the like, the aralkyl group may be substituted; (C2-C8)alkanoyl group such as ethanoyl, propanoyl, butanoyl and the like, the (C2-C8)alkanoyl group may be substituted; (C3-C8)alkenoyl group such as propenoyl, butenoyl, pentenoyl and the like, (C3-C8)alkenoyl group may be substituted; aroyl group such as benzoyl and the like, the aroyl group may be substituted; heteroaroyl group such as pyridyl carbonyl, furyl carbonyl and the like; the heteroaroyl group may be substituted; aralkenoyl group such as phenylpropenoyl, phenylbutenoyl, phenylpentenoyl and the like, the aralkenoyl group may be substituted; aralkanoyl group such as phenylpropanoyl, phenylbutanoyl, phenylpentanoyl and the like, the aralkanoyl group may be substituted; sulfonyl group such as methanesulfonyl, benzenesulfonyl, p-toluenesulfonyl and the like, the sulfonyl group may be substituted or a group xe2x80x94(CO)xe2x80x94NHxe2x80x94R7 where R7 represents linear or branched (C1-C8)alkyl group such as methyl, ethyl, n-propyl, iso-propyl and the like, (C1-C8)alkyl group may be substituted; aryl group such as phenyl, naphthyl and the like, the aryl group may be substituted; aralkyl such as benzyl, phenethyl and the like, the aralkyl group may be substituted.
The substituents on R1, Ra, Rb, R2, R3 and R6 may be selected from cyano, hydroxy, nitro, thio, halogen atom such as fluorine, chlorine, bromine and the like; substituted or unsubstituted groups selected from linear or branched (C1-C8) alkyl group such as methyl, ethyl, n-propyl, iso-propyl and the like; amino, mono or disubstituted amino group, alkanoyl group such as ethanoyl, propanoyl, butanoyl and the like; thio(C1-C8)alkyl such as thiomethyl, thioethyl, thiopropyl and the like; (C1-C6) alkoxy group such as methoxy, ethoxy, propyloxy, butyloxy and the like; aroyl group such as benzoyl and the like; acyloxy group such as acetyloxy, propanoyloxy, butanoyloxy and the like; aryl group such as phenyl, naphthyl and the like, the aryl group may be mono or disubstituted, heteroaryl group such as pyridyl, furyl, thienyl and the like; acylamino groups such as CH3CONH, C2H5CONH, C3H7CONH, C4H9CONH and C6H5CONH; aralkylamino group such as C6H5CH2NH, C6H5CH2CH2NH, C6H5CH2NCH3 and the like; alkoxycarbonylamino group such as C4H9OCONH, C2H5OCONH, CH3OCONH and the like; aryloxycarbonylamino group such as C6H5OCONH, C6H5OCONCH3, C6H5OCONC2H5, C6H4(CH3)OCONH, C6H4(OCH3)OCONH, and the like; aralkoxycarbonylamino group such as C6H5CH2OCONH, C6H5CH2CH2OCONH, C6H5CH2OCON(CH3), C6H5CH2OCON(C2H5), C6H4(CH3)CH2OCONH, C6H4(OCH3)CH2OCONH and the like; (C1-C8) alkylthio group such as methylthio, ethylthio, propylthio and the like; heteroarylthio group such as pyridylthio, furylthio, thiophenylthio, benzothiazolethio, purinethio, benzimidazolethio, pyrimidinethio and the like; acylthio group such as acetylthio, propanoylthio, butanoylthio and the like; aralkylthio group such as benzylthio, phenylethylthio, phenylpropylthio and the like; arylthio group such as phenylthio, napthylthio and the like; (C1-C8)alkylseleno such as methylseleno, ethylseleno, propylseleno, isopropylseleno and the like; acylseleno such as acetylseleno, propionylseleno and the like; aralkylseleno such as benzylseleno, phenylethylseleno, phenylpropylseleno and the like; arylseleno such as phenylseleno, napthylseleno and the like or COOR, where R represents hydrogen or (C1-C6) alkyl groups. The substituents are selected from halogen, hydroxy, nitro, cyano, amino, (C1-C6)alkyl, aryl or (C1-C6)alkoxy group.
The substituents on R7 may be selected from hydroxy, halogen atom such as fluorine, chlorine or bromine, nitro, cyano, (C1-C6)alkyl, aryl, or aralkyl. These groups are as defined in R7.
Suitable groups represented by R8 include substituted or unsubstituted (C1-C6) alkyl such as methyl, ethyl, n-propyl and the like; aryl group such as phenyl, naphthyl and the like, the aryl group may be substituted; aralkyl such as benzyl, phenethyl and the like, the aralkyl group may be substituted; aroyl group such as benzoyl and the like, the aroyl group may be substituted. The substituents on the alkyl group, aromatic moiety of the aryl group, aralkyl group or aroyl group include halogen atom such as fluorine, chlorine and bromine; amino group, cyano, hydroxy, nitro, trifluoroethyl, (C1-C6) alkyl, or (C1-C6) alkoxy.
When the groups R1, Ra, Rb, R2, R3, R6, R7 or R8 represent disubstituted aryl, the two substituents on the adjacent carbon atoms form a linking group such as xe2x80x94Xxe2x80x94CH2xe2x80x94Yxe2x80x94, xe2x80x94Xxe2x80x94CH2xe2x80x94CH2xe2x80x94Y, where X and Y may be same or different and independently represent O, NH, S or CH2.
When the groups represented by Ra, Rb, R1, R2, R3, R6, R7 or R8 are multi substituted, the substituents present on the two adjacent carbons may form a linking group xe2x80x94Xxe2x80x94(CR12R13)nxe2x80x94Yxe2x80x94 where R12 and R13 represent (C1-C8) alkyl such as methyl, ethyl the like, X and Y may be same or different and independently represent CH2, O, S, NH; and n=1 or 2.
Pharmaceutically acceptable salts forming part of this invention include salts derived from inorganic bases such as Li, Na, K, Ca, M, Fe, Cu, Zn, and Mn; salts of organic bases such as N,Nxe2x80x2-diacetylethylenediamine, betaine, caffeine, 2-diethylaminoethanol, 2-dimethylaminoethanol, N-ethylmorpholine, N-ethylpiperidine, glucamine, glucosamine, hydrabamine, isopropylamine, methylglucamine, morpholine, piperazine, piperidine, procaine, purines, theobromine, triethylamine, trimethylamine, tripropylamine, tromethamine, diethanolamine, meglumine, ethylenediamine, N,Nxe2x80x2-diphenylethylenediamine, N,Nxe2x80x2-dibenzylethylenediamine, N-benzyl phenylethylamine, choline, choline hydroxide, dicyclohexylamine, metformin, benzylamine, phenylethylamine, dialkylamine, trialkylamine, thiamine, aminopyrimidine, aminopyridine, purine, spermidine, and the like; chiral bases like alkylphenylamine, glycinol, phenyl glycinol and the like, salts of natural amino acids such as glycine, alanine, valine, leucine, isoleucine, norleucine, tyrosine, cystine, cysteine, methionine, proline, hydroxy proline, histidine, ornithine, lysine, arginine, serine, threonine, and phenylalanine; unnatural amino acids such as D-isomers or substituted amino acids; guanidine, substituted guanidine wherein the substituents are selected from nitro, amino, alkyl, alkenyl, alkynyl, ammonium or substituted ammonium salts and aluminum salts. Salts may include acid addition salts where appropriate which are, sulphates, nitrates, phosphates, perchlorates, borates, hydrohalides, acetates, tartrates, maleates, citrates, succinates, palmoates, methanesulphonates, benzoates, salicylates, hydroxynaphthoates, benzenesulfonates, ascorbates, glycerophosphates, ketoglutarates and the like. Pharmaceutically acceptable solvates may be hydrates or comprise other solvents of crystallization such as alcohols.
Particularly usefuil compounds of the present invention include:
3,19-Diacetyl-12-(N-benzylamino)-14-deoxy andrographolide;
3,19-Diacetyl-12xcex1-(N-benzylamino)-14-deoxy andrographolide;
3,19-Diacetyl-12xcex2-(N-benzylamino)-14-deoxy andrographolide;
14-Deoxy-12-(O-methylphenylglycino)-3,19-O-(1-phenylethylidene)andrographolide;
14-Deoxy-12xcex1-(O-methylphenylglycino)-3,19-O-(1-phenylethylidene)andrographolide;
14-Deoxy-12xcex2-(O-methylphenylglycino)-3,19-O-(1-phenylethylidene)andrographolide;
3,19-Diacetyl-14-deoxy-12-(N-4-methoxybenzylamino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-(N-4-methoxybenzylamino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-(N-4-methoxybenzylamino)andrographolide;
3,19-Diacetyl-12-(N-2-chlorobenzylamino)-14-deoxy andrographolide;
3,19-Diacetyl-12xcex1-(N-2-chlorobenzylamino)-14-deoxy andrographolide;
3,19-Diacetyl-12-xcex2(N-2-chlorobenzylamino)-14-deoxy andrographolide;
3,19-Diacetyl-14-deoxy-12-(O-methylproino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-(O-methylprolino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-(O-methylprolino)andrographolide;
3,19-Diacetyl-14-deoxy-12-(O-methylphenylalano)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-(O-methylphenylalanino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-(O-methylphenylalanino)andrographolide;
3,19-Diacetyl-14-deoxy-12-(O-methyl-3-phenylisoserino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-(O-methyl-3-phenylisoserino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-(O-methyl-3-phenylisoserino)andrographolide;
3,19-Diacetyl-14-deoxy-12-(O-methylmethionino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-(O-methylmethionino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-(O-methylmethionino)andrographolide;
3,19-Diacetyl-14-deoxy-12-(O-methylphenylglycino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-(O-methylphenylglycino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-(O-methylphenylglycino)andrographolide;
3,19-Diacetyl-14-deoxy-12-(O-methylalanino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-(O-methylalanino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-(O-methylalanino)andrographolide;
3,19-Diacetyl-14-deoxy-12-(O-methylglycino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-(O-methylgycino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-(O-methylglycino)andrographolide;
3,19-Diacetyl-14-deoxy-12-(O-methylselenomethionino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-(O-methylselenomethionino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-(O-methylselenomethionino)andrographolide;
3,19-Diacetyl-14-deoxy-12-N-imidazolyl)androgapholide;
3,19-Diacetyl-14-deoxy-12xcex1-(N-imidazolyl)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-(N-imidazolyl)andrographolide;
3,19-Diacetyl-14-deoxy-12-(N-methypiperazino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-(N-methypiperazino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-(N-methylpiperazino)andrographolide;
3,19-Diacetyl-14-deoxy-12-morpholino andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-morpholino andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-morpholino andrographolide;
3,19-Diacetyl-12-(N-acetylpiperazino)-14-deoxy andrographolide;
3,19-Diacetyl-12xcex1-(N-acetylpiperazino)-14-deoxy andrographolide;
3,19-Diacetyl-12xcex2-(N-acetylpiperazino)-14-deoxy andrographolide;
12-(N-Benzylamino)-14-deoxy andrographolide;
12xcex1-(N-Benzylamino)-14-deoxy andrographolide;
12xcex2-(N-Benzylamino)-14-deoxy andrographolide;
14-Deoxy-12-(O-methylphenylglycino)andrographolide;
14-Deoxy-12xcex1-(O-methylphenylglycino)andrographolide;
14-Deoxy-12xcex2-(O-methylphenylglycino)andrographolide;
14-Deoxy-3,19-O-isopropylidene-12-(methylphenylalanino)andrographolide;
14-Deoxy-3,19-O-isopropylidene-12xcex1-(methylphenylalanino)andrographolide;
14-Deoxy-3,19-O-isopropylidene-12xcex2-(methylphenylalanino)andrographolide;
12-(N-Benzylamino)-14-deoxy-3,19-O-(1-phenylethylidene)andrographolide;
12xcex1-(N-Benzylamino)-14-deoxy-3,19-O-(1-phenylethylidene)andrographolide;
12xcex2-(N-Benzylamino)-14-deoxy-3,19-O-(1-phenylethylidene)andrographolide;
14-Deoxy-12-(O-methylphenylalanino)-3,19-O-(1-phenylethylidene)andrographolide;
14-Deoxy-12xcex1-(O-methylphenylalanino)-3,19-O-(1-phenylethylidene)andrographolide;
14-Deoxy-12xcex2-(O-methylphenylalanino)-3,19-O-(1-phenylethylidene)andrographolide;
14-Deoxy-12-(O-methylprolino)-3,19-O-(1-phenylethylidene)andrographolide;
14-Deoxy-12xcex1-(O-methylprolino)-3,19-O-(1-phenylethylidene)andrographolide;
14-Deoxy-12xcex2-(O-methylprolino)-3,19-O-(1-phenylethylidene)andrographolide;
3,19-O-Benzylidene-12-(N-benzylamino)-14-deoxy andrographolide;
3,19-O-Benzylidene-12xcex1-(N-benzylamino)-14-deoxy andrographolide;
3,19-O-Benzylidene-12xcex2-(N-benzylamino)-14-deoxy andrographolide;
3,19-Diacetyl-14-deoxy-8,17-epoxy-12-(O-methylnethionino)andrographolide;
3,19-Diacetyl-14-deoxy-8,17-epoxy-12xcex1-(O-methylmethionino)andrographolide;
3,19-Diacetyl-14-deoxy-8,17-epoxy-12xcex2-(O-methylmethionino)andrographolide;
3,19-Diacetyl-14-deoxy-8,17-epoxy-12-(O-methylphenylglycino)andrographolide;
3,19-Diacetyl-14-deoxy-8,17-epoxy-12xcex1-(O-methylphenylglycino)andrographolide;
3,19-Diacetyl-14-deoxy-8,17-epoxy-12xcex2-(O-methylphenylglycino)andrographolide;
3,19-Diacetyl-14-deoxy-12-(N-1,2,4-triazolyl)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-(N-1,2,4-triazolyl)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-(N-1,2,4-triazolyl)andrographolide;
14-Deoxy-12-(2,3-dimethylanilino)andrographolide;
14-Deoxy-12xcex1-(2,3-dimethylanilino)andrographolide;
14-Deoxy-12xcex2-(2,3-dimethylanilino)andrographolide;
3,19-Diacetyl-14-deoxy-12-(4-methoxy-2-methylanilino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-(4-methoxy-2-methylanilino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-(4-methoxy-2-methylanilino)andrographolide;
3,19-Diacetyl-14-deoxy-12-(4-hydroxy-2-methylanilino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-(4-hydroxy-2-methylanilino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-(4-hydroxy-2-methylanilino)andrographolide;
3,19-Diacetyl-14-deoxy-12-(2-mercaptoanilino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-(2-mercaptoanilino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-(2-mercaptoanilino)andrographolide;
3,19-Diacetyl-14-deoxy-12-(3,4-dimethoxyanilino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-(3,4-dimethoxyanilino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-(3,4-dimethoxyanilino)andrographolide;
3,19-Diacetyl-12-anilino-14-deoxy andrographolide;
3,19-Diacetyl-12xcex1-anilino-14-deoxy andrographolide;
3,19-Diacetyl-12xcex2-anilino-14-deoxy andrographolide;
3,19-Diacetyl-14-deoxy-12-(2,3-dimethylanilino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-(2,3-dimethylanilino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-(2,3-dimethylanilino)andrographolide;
3,19-Diacetyl-14-deoxy-12-(2-methyl-4-methylsulfonateanilino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-(2-methyl-4-methylsulfonateanilino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-(2-methyl-4-methylsulfonateanilino)andrographolide;
3,19-Diacetyl-14-deoxy-12-(2-tetrazolylamino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-(N-tetrazolylamino)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-(N-tetrazolylamino)andrographolide;
14-Deoxy-12-(3,4-dimethoxyanilino)andrographolide;
14-Deoxy-12xcex1-(3,4-dimethoxyanilino)andrographolide;
14-Deoxy-12xcex2-(3,4-dimethoxyanilino)andrographolide;
14-Deoxy-3,19-O-isopropylidene-12-(2,3-dimethylanilino)andrographolide;
14-Deoxy-3,19-O-isopropylidene-12xcex1-(2,3-dimethylanilino)andrographolide;
14-Deoxy-3,19-O-isopropylidene-12xcex2-(2,3-dimethylanilino)andrographolide;
14-Deoxy-12-(2-methylanilino)-3,19-O-(1-phenylethylidene)andrographolide;
14-Deoxy-12xcex1-(2-methylanilino)-3,19-O-(1-phenylethylidene)andrographolide;
14-Deoxy-12xcex2-(2-methylanilino)-3,19-O-(1-phenylethylidene)andrographolide;
3,19-O-Benzylidene-14-deoxy-12-(2,3-dimethylanilino)andrographolide;
3,19-O-Benzylidene-14-deoxy-12xcex1-(2,3-dimethylanilino)andrographolide;
3,19-O-Benzylidene-14-deoxy-12xcex2-(2,3-dimethylanilino)andrographolide;
3,19-Diacetyl-12-anilino-14-deoxy-8,17-epoxy andrographolide;
3,19-Diacetyl-12xcex1-anilino-14-deoxy-8,17-epoxy andrographolide;
3,19-Diacetyl-12xcex2-anilino-14-deoxy-8,17-epoxy andrographolide;
3,19-Diacetyl-14-deoxy-8,17-epoxy-12-(2,3-dimethylanilino)andrographolide;
3,19-Diacetyl-14-deoxy-8,17-epoxy-12xcex1-(2,3-dimethylanilino)andrographolide;
3,19-Diacetyl-14-deoxy-8,17-epoxy-12xcex2-(2,3-dimethylanilino)andrographolide;
14-Deoxy-12-(N1-uracil)andrographolide;
14-Deoxy-12xcex1-(N1-uracil)andrographolide;
14-Deoxy-12xcex2-(N1-uracil)andrographolide;
3,19-Diacetyl-14-deoxy-12-[N-(1,2-dihydro-2-pyrimidinone)amino]-1-andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-[N-(1,2-dihydro-2-pyrimidinone)amino]-1-andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-[N-(1,2-dihydro-2-pyrimidinone)amino]-1-andrographolide;
3,19-Diacetyl-14-deoxy-12-(N1-uracil)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-(N1-uracil)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-(N1-uracil)andrographolide;
3,19-Diacetyl-14-deoxy-12-[N1-(5-chlorouracil)]andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-[N1-(5-chlorouracil)]andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-[N1-(5-chlorouracil)]andrographolide;
3,19-Diacetyl-14-deoxy-12-[N1-(5-bromouracil)]andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-[N1-(5-bromouracil)]andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-[N1-(5-bromouracil)]andrographolide;
3,19-Diacetyl-14-deoxy-12-[N1-(5-fluorouracil]andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-[N1-(5-fluorouracil]andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-[N1-(5-fluorouracil)]andrographolide;
3,19-Diacetyl-14-deoxy-12-[N1-(5-iodouracil)]andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-[N1-(5-iodouracil)]andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-[N1-(5-iodouracil)]andrographolide;
14-Deoxy-12-[N-(1,2-dihydro-2-pyrimidinone)amino]andrographolide;
14-Deoxy-12xcex1-[N-(1,2-dihydro-2-pyrimidinone)amino]andrographolide;
14-Deoxy-12xcex2-[N-(1,2-dihydro-2-pyrimidinone)amino]andrographolide;
14-Deoxy-12-[N1-(5-fluorouracil)]andrographolide;
14-Deoxy-12xcex1-[N-(5-fluorouracil)]andrographolide;
14-Deoxy-12xcex2-[N1-(5-fluorouracil)]andrographolide;
14-Deoxy-12-[N1-(5-bromouracil)]andrographolide;
14-Deoxy-12xcex1-[N1-(5-bromouracil)]andrographolide;
14-Deoxy-12xcex2-[N1-(5-bromouracil)]andrographolide;
14-Deoxy-12-[N1-(5-iodouracil)]andrographolide;
14-Deoxy-12xcex1-[N1-(5-bodouracil)]andrographolide;
14-Deoxy-12xcex2-[N1-(5-iodouracil)]andrographolide;
14-Deoxy-8,17-epoxy-12-phenylthio andrographolide;
14-Deoxy-8,17-epoxy-12xcex1-phenylthio andrographolide;
14-Deoxy-8,17-epoxy-12xcex2-phenylthio andrographolide;
3,19-Diacetyl-14-deoxy-12-phenylseleno andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-phenylseleno andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-phenylseleno andrographolide;
12-(C-Benzoylmethyl)-14-deoxy-13,19-O-(1-phenylethylidene)andrographolide;
12xcex1-(C-Benzoylmethyl)-14-deoxy-13,19-O-(1-phenylethylidene)andrographolide;
12xcex2-(C-Benzoylmethyl)-14-deoxy-13,19-O-(1-phenylethylidene)andrographolide;
14-Deoxy-3,19-O-isopropylidene-12-ethylthio andrographolide;
14-Deoxy-3,19-O-isopropylidene-12xcex1-ethylthio andrographolide;
14-Deoxy-3,19-O-isopropylidene-12xcex2-ethylthio andrographolide;
3,19-Diacetyl-14-deoxy-12-phenylthio andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-phenylthio andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-phenylthio andrographolide;
3,19-Diacetyl-14-deoxy-12-acetylthio andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-acetylthio andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-acetylthio andrographolide;
3,19-Diacetyl-14-deoxy-12-ethylthio andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-ethylthio andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-ethylthio andrographolide;
3,19-Diacetyl-12-benzyl-14-deoxy andrographolide;
3,19-Diacetyl-12xcex1-benzyl-14-deoxy andrographolide;
3,19-Diacetyl-12xcex2-benzyl-14-deoxy andrographolide;
3,19-Diacetyl-14-deoxy-12-(1,1xe2x80x2-diethyl dicarboxylate methyl)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-(1,1xe2x80x2-diethyl dicarboxylate methyl)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-(1,1xe2x80x2-diethyl dicarboxylate methyl)andrographolide;
14-Deoxy-12-phenylthio andrographolide;
14-Deoxy-12xcex1-phenythio andrographolide;
14-Deoxy-12xcex2-phenylthio andrographolide;
14-Deoxy-12-ethylthio andrographolide;
14-Deoxy-12xcex1-ethylthio andrographolide;
14-Deoxy-12xcex2-ethylthio andrographolide;
14-Deoxy-12-phenylseleno andrographolide;
14-Deoxy-12xcex1-phenylseleno andrographolide;
14-Deoxy-12xcex2-phenylseleno andrographolide;
14-Deoxy-3,19-O-isopropylidene-12-phenylthio andrographolide;
14-Deoxy-3,19-O-isopropylidene-12xcex1-phenylthio andrographolide;
14-Deoxy-3,19-O-isopropylidene-12xcex2-phenylthio andrographolide;
14-Deoxy-3,19-O-(1-phenylethylidene)-12-phenylthio andrographolide;
14-Deoxy-3,19-O-(1-phenylethylidene)-12xcex1-phenylthio andrographolide;
14-Deoxy-3,19-O-(1-phenylethylidene)-12xcex2-phenylthio andrographolide;
14-Deoxy-3,19-O-(1-phenylethylidene)-12-ethylthio andrographolide;
14-Deoxy-3,19-O-(1-phenylethylidene)-12xcex1-ethylthio andrographolide;
14-Deoxy-3,19-O-(1-phenylethylidene)-12xcex2-ethylthio andrographolide;
3,19-O-Benzylidene-14-deoxy-12-phenylthio andrographolide;
3,19-O-Benzylidene-14-deoxy-12xcex1-phenylthio andrographolide;
3,19-O-Benzylidene-14-deoxy-12xcex2-phenylthio andrographolide;
3,19-Diacetyl-14-deoxy-8,17-epoxy-12-phenylthio andrographolide;
3,19-Diacetyl-14-deoxy-8,17-epoxy-12xcex1-phenylthio andrographolide;
3,19-Diacetyl-14-deoxy-8,17-epoxy-12xcex2-phenylthio andrographolide;
12-Cinnamoyloxy-14-deoxy andrographolide;
12xcex1-Cinnamoyloxy-14-deoxy andrographolide;
12xcex2-Cinnamoyloxy-14-deoxy andrographolide;
12-Cinnamoyloxy-14-deoxy-8,17-epoxy andrographolide;
12xcex1-Cinnamoyloxy-14-deoxy-8,17-epoxy andrographolide;
12xcex2-Cinnamoyloxy-14-deoxy-8,17-epoxy andrographolide;
14-Deoxy-12-hydroxy andrographolide;
14-Deoxy-12xcex1-hydroxy andrographolide;
14-Deoxy-12xcex2-hydroxy andrographolide;
12-Acetoxy-3,19-diacetyl-14-deoxy andrographolide;
12xcex1-Acetoxy-3,19-diacetyl-14-deoxy andrographolide;
12xcex2-Acetoxy-3,19-diacetyl-14-deoxy andrographolide;
3,19-Diacetyl-14-deoxy-12-methoxy andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-methoxy andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-methoxy andrographolide;
3,19-Diacetyl-14-deoxy-12-(2-acetoxy-3-N-acetylamino-3-phenylpropionyloxy)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-(2-acetoxy-3-N-acetylamino-3-phenylpropionyloxy)andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-(2-acetoxy-3-N-acetylamino-3-phenylpropionyloxy)andrographolide;
12-(N-Boc glycinyloxy)-14-deoxy-8,17-epoxy-3,19-dipropionyl andrographolide;
12xcex1-(N-Boc glycinyloxy)-14-deoxy-8,17-epoxy-3,19-dipropionyl andrographolide;
12xcex2-(N-Boc glycinyloxy)-14-deoxy-8,17-epoxy-3,19-dipropionyl andrographolide;
3,19-Diacetyl-14-deoxy-12-mercaptobenzothiazolyl andrographolide;
3,19-Diacetyl-14-deoxy-12xcex1-mercaptobenzothiazolyl andrographolide;
3,19-Diacetyl-14-deoxy-12xcex2-mercaptobenzothiazolyl andrographolide;
3,19-Diacetyl-12-(N,N-benzylchloroacetyl)amino-14-deoxy-12 andrographolide;
3,19-Diacetyl-12xcex1-(N,N-benzylchloroacetyl)amino-14-deoxy-12-andrographolide; and
3,19-Diacetyl-12xcex2-(N,N-benzylchloroacetyl)amino-14-deoxy-12-andrographolide.
The present invention also provides a process for the preparation of novel derivatives of andrographolide of the general formula (I), where R1 represents hydrogen, halogen, thio, or substituted or unsubstituted alkyl, alkylthio, heteroarylthio, acylthio, aralkylthio, arylthio, alkylseleno, acylseleno, aralkylseleno, arylseleno, NRaRb where Ra, and Rb may be same or different and independently represent hydrogen, or substituted or unsubstituted alkyl, aryl, acyl, aralkyl, heteroaryl, haloalkyl, or haloacyl or Ra and Rb together with the nitrogen atom to which they are attached may form substituted or unsubstituted 5 or 6 membered cyclic ring system containing carbon atoms, at least one nitrogen and optionally one or more hetero atoms selected from oxygen, sulfur or nitrogen, the cyclic ring system may contain one or two double bonds or it may be aromatic or R1 may represent OR6 where R6 represents hydrogen or substituted or unsubstituted groups selected from alkyl, aryl, aralkyl, alkenoyl, alkanoyl, aroyl, heteroaroyl, aralkenoyl, aralkanoyl, sulfonyl groups or a group xe2x80x94(CO)xe2x80x94NHxe2x80x94R7 where R7 represents substituted or unsubstituted groups selected from alkyl, aryl, or aralkyl; R2 and R3 may be same or different and independently represent hydrogen or substituted or unsubstituted groups selected from alkyl, aryl, heteroaryl, aralkyl, heteroaralkyl, alkanoyl, alkenoyl, aroyl, heteroaroyl, aralkenoyl, aralkanoyl, sulfonyl group or a group xe2x80x94(CO)xe2x80x94Wxe2x80x94R8 where W represents O, S or NR9, wherein R9 represents hydrogen or (C1-C6)alkyl group, R8 represents substituted or unsubstituted groups selected from alkyl, aryl, aralkyl or aroyl or OR2 and OR3 together form a substituted or unsubstituted 6 or 7 membered cyclic structure containing carbon and oxygen atoms; R4 and R5 together represents xe2x95x90CH2 or an epoxide group; their stereoisomers, their polymorphs, their pharmaceutically acceptable salts or their pharmaceutically acceptable solvates, which comprises:
(i) protecting andrographolide derivative of the formula (VII), 
where R4 and R5 are as defined earlier, to produce a compound of formula (VIII), 
where P1 and P2 may be same or different and represent hydrogen, trityl, t-butyl dimethyl silyl, pivaloyl and the like or esters such as acetate, propionate, benzoate and the like or together may form methylene dioxy, isopropylidene, benzylidene, 1-phenyl ethylidene and the like; and R4 and R5 are as defined earlier,
(iii) converting the compound of formula (VIII) to a compound of formula (IX), 
where Y represents halogen atom such as fluorine, chlorine, bromine, iodine or esters such as sulfonyl chloride, acetate, propionate, benzoate and the like or sulfonyl esters such as mesylate, tosylate, triflate and the like; P1 and p2 may be same or different and represent hydrogen, trityl, t-butyl dimethyl silyl, pivaloyl and the like or esters such as acetate, propionate, benzoate and the like or together may form methylene dioxy, isopropylidene, benzylidene, 1-phenyl ethylidene and the like; and R4 and R5 are as defined earlier,
(iii) reacting andrographolide derivative of the formula (IX) with a suitable nucleophile to produce a compound of formula (X) 
where all symbols are as defined earlier and if desired,
(iv) deprotecting the compound of formula (X) by conventional methods to produce a compound of formula (XI), 
where all symbols are as defined earlier and
(v) reacting the compound of formula (XI) with R2-L and/or R3-L, where L represents a leaving group such as hydroxy, halogen atom like fluorine, chlorine, bromine, or iodine; p-toluenesulfonate, methanesulfonate, trifluoromethanesulfonate; or acyl groups such as acetate, propanoate, butanoate and the like; and R2 and R3 are as defined above to produce a compound of formula (I), and if desired,
(vi) converting compound of formula (I) into its stereoisomers, and/or pharmaceutical salts by conventional methods.
The protection of a compound of formula (VII) may be carried out using trityl chloride, t-butyldimethylsilyl chloride, pivaloyl chloride, dimethylsulfoxide, acetone, 2,2-dimethoxy propane, trimethyl ortho acetate, benzaldehyde, p-methoxy benzaldehyde, acetophenone and the like. The reaction may be carried out in the presence of a suitable catalyst such as SOCl2, H2SO4, HClO4, pyridinium p-toluene sulphonate, pyridine, p-toluene sulfonic acid, dimethyl aminopyridine, and the like. The reaction may be carried out in the absence or presence of suitable solvent such as benzene, DMF, dimethylsulfoxide (DMSO), acetonitrile, dichloromethane (DCM), and the like or mixtures thereof. The reaction may be carried out at a temperature in the range of 0xc2x0 C. to 60xc2x0 C., preferably at a temperature in the range of 20xc2x0 C. to 40xc2x0 C. The reaction time may range from 2 to 6 h, preferably from 2 to 4 h.
The conversion of compound of formula (VIII) to compound of formula (IX) may be carried out using halogenating agents such as thionyl chloride, thionyl bromide, phosphonyl chloride, PCl5, PBr3, bromine trifluoride, N-bromosuccinimide-hydrogen fluoride (NBS-HF), cobalt (III) fluoride, lithium fluoride, potassium fluoride, sodium fluoride, cesium fluoride, potassium iodide, sodium, iodide, iodine, iodine cerium (IV) ammonium nitrate, or R-L where R is acetyl, propionyl, benzoyl, mesyl, tosyl, triflyl and the like and L is as defined above. The reaction may be carried out in the presence of solvents such as ether, dichloromethane, chloroform, DMF, DMSO and the like. The reaction may be carried out in the range of xe2x88x9240xc2x0 C. to 160xc2x0 C. The duration of the reaction may range from 1 to 6 h.
The reaction of compound of formula (IX) with nucleophiles such as aniline, benzylamine, arylthio, piperazine, morpholine, imidazole, aminotetrazole, triazole, esters of xcex1-aminoacids, esters of xcex2-amino acids, acetic acid, thioacetic acid, alkyl magnesium halide, aryl magnesium halide, methanol, ethanol, propanol and the like may be carried out in the presence of solvents such as ether, DCM, DMF, and the like. The reaction may be carried out in the absence or presence of alumina. The reaction temperature may range from 80xc2x0 C. to 100xc2x0 C. and the reaction time may range from 1-10 h.
The deprotection of a compound of formula (X) to produce a compound of formula (XI) may be carried out using deprotecting agent such as acetic acid, hydrochloric acid, formic acid, trifluoroacetic acid and the like. The reaction may be carried in the presence of suitable solvent such as water, THF, dioxane, DCM, CHCl3, methanol and the like or mixtures thereof. The reaction may be carried out at a temperature in the range of 0xc2x0 C. to 60xc2x0 C., preferably at a temperature in the range of 20xc2x0 C. to 40xc2x0 C. The reaction time may range from 2 to 6 h, preferably from 2 to 4 h.
The reaction of compound of formula (XI) with R2-L and R3-L, to produce a compound of formula (I) may be carried out in the presence of dicyclohexylcarbodiimide (DCC), diethyl azadicarboxylate (DEAD), diisopropyl azadicarboxylate (DIAD) and the like. The reaction may be carried out in the absence or presence of a base selected from triethylamine, pyridine, dimethyl aminopyridine and the like. The reaction may be carried out in the presence of solvents such as dichloromethane, chloroform, C6H6, dimethyl sulfoxide, methanol, ethanol and the like or mixtures thereof. The reaction may be carried out at a temperature in the range of 0xc2x0 C. to 200xc2x0 C., preferably at a temperature in the range of 20xc2x0 C. to 160xc2x0 C. and the reaction time may range from 2 to 12 h, preferably from 2 to 10 h.
In yet another embodiment of the present invention, there is provided a novel intermediate of formula (IX) 
where Y represents halogen atom such as fluorine, chlorine, bromine, iodine or esters such as sulfonyl chloride, acetate, propionate, benzoate and the like or sulfonyl esters such as mesylate, tosylate, triflate and the like; P1 and P2 may be same or different and represent hydrogen, trityl, t-butyl dimethyl silyl, pivaloyl and the like or esters such as acetate, propionate, benzoate and the like or together may form methylene dioxy, isopropylidene, benzylidene, 1-phenyl ethylidene and the like; and R4 and R5 together represent xe2x95x90CH2 or an epoxide group.
The present invention also provides a process for the preparation of compound of formula (IX), their stereoisomers, their polymorphs, their pharmaceutically acceptable salts or their pharmaceutically acceptable solvates, which comprises:
(i) protecting andrographolide derivative of the formula (VII), 
where R4 and R5 are as defined earlier, to produce a compound of formula (VIII), 
where P1 and P2 may be same or different and represent hydrogen, trityl, t-butyl dimethyl silyl, pivaloyl and the like or esters such as acetate, propionate, benzoate and the like or together may form methylene dioxy, isopropylidene, benzylidene, 1-phenyl ethylidene and the like; and R4 and R5 are as defined earlier,
(ii) converting the compound of formula (VIII) to a compound of formula (IX), 
where Y represents halogen atom such as fluorine, chlorine, bromine, iodine or esters such as sulfonyl chloride, acetate, propionate, benzoate and the like or sulfonyl esters such as mesylate, tosylate, triflate and the like; P1 and P2 may be same or different and represent hydrogen, trityl, t-butyl dimethyl silyl, pivaloyl and the like or esters such as acetate, propionate, benzoate and the like or together may form methylene dioxy, isopropylidene, benzylidene, 1-phenyl ethylidene and the like; and R4 and R5 are as defined earlier.
The protection of a compound of formula (VII) may be carried out using trityl chloride, t-butyldimethylsilyl chloride, pivaloyl chloride, dimethylsulfoxide, acetone, 2,2-dimethoxy propane, trimethyl ortho acetate, benzaldehyde, p-methoxy benzaldehyde, acetophenone and the like. The reaction may be carried out in the presence of a suitable catalyst such as SOCl2, H2SO4, HClO4, pyridinium p-toluene sulphonate, pyridine, p-toluene sulfonic acid, dimethyl aminopyridine, and the like. The reaction may be carried out in the absence or presence of suitable solvent such as benzene, DMF, dimethylsulfoxide (DMSO), acetonitrile, dichloromethane (DCM), and the like or mixtures thereof. The reaction may be carried out at a temperature in the range of 0xc2x0 C. to 60xc2x0 C., preferably at a temperature in the range of 20xc2x0 C. to 40xc2x0 C. The reaction time may range from 2 to 6 h, preferably from 2 to 4 h.
The conversion of compound of formula (VIII) to compound of formula (IX) may be carried out using halogenating agents such as thionyl chloride, thionyl bromide, phosphonyl chloride, PCl5, PBr3, bromine trifluoride, N-bromosuccinimide-hydrogen fluoride (NBS-HF), cobalt (III) fluoride, lithium fluoride, potassium fluoride, sodium fluoride, cesium fluoride, potassium iodide, sodium, iodide, iodine, iodine cerium (IV) amnmonium nitrate, or R-L where R is acetyl, propionyl, benzoyl, mesyl, tosyl, triflyl and the like and L is as defined above. The reaction may be carried out in the presence of solvents such as ether, dichloromethane, chloroform, DMF, DMSO and the like; The reaction may be carried out in the range of xe2x88x9240xc2x0 C. to 160xc2x0 C. The duration of the reaction may range from 1 to 6 h.
In yet another embodiment of the present invention, there is provided a novel intermediate of formula (X) 
where R1 represents hydrogen, halogen, thio, or substituted or unsubstituted alkyl, alkylthio, heteroarylthio, acylthio, aralkylthio, arylthio, alkylseleno, acylseleno, aralkylseleno, arylseleno, NRaRb where Ra, and Rb may be same or different and independently represent hydrogen, or substituted or unsubstituted alkyl, aryl, acyl, aralkyl, heteroaryl, haloalkyl, haloacyl or Ra and Rb together with the nitrogen atom to which they are attached may form substituted or unsubstituted 5 or 6 membered cyclic ring system containing carbon atoms, at least one nitrogen atom and optionally one or more hetero atoms selected from oxygen, sulfur or nitrogen, the cyclic ring system may contain one or two double bonds or it may be aromatic or R1 may represent OR6 where R6 represents hydrogen or substituted or unsubstituted groups selected from alkyl, aryl, or aralkyl, alkenoyl, alkanoyl, aroyl, heteroaroyl, aralkenoyl, aralkanoyl, sulfonyl groups or a group xe2x80x94(CO)xe2x80x94NHxe2x80x94R7 where R7represents substituted or unsubstituted groups selected from alkyl, aryl, or aralkyl; P1 and P2 may be same or different and represent hydrogen, trityl, t-butyl dimethyl silyl, pivaloyl and the like or esters such as acetate, propionate, benzoate and the like or together may form methylene dioxy, isopropylidene, benzylidene, 1-phenyl ethylidene and the like; R4 and R5 together represents xe2x95x90CH2 or an epoxide group.
The present invention also provides a process for the preparation of novel intermediates of the formula (X), their stereoisomers, their polymorphs, their pharmaceutically acceptable salts or their pharmaceutically acceptable solvates, which comprises:
(i) protecting andrographolide derivative of the formula (VII), 
where R4 and R5 are as defined earlier, to produce a compound of formula (VIII), 
where P1 and P2 may be same or different and represent hydrogen, trityl, t-butyl dimethyl silyl, pivaloyl and the like or esters such as acetate, propionate, benzoate and the like or together may form methylene dioxy, isopropylidene, benzylidene, 1-phenyl ethylidene and the like; and R4 and R5 are as defined earlier,
(ii) converting the compound of formula (VIII) to a compound of formula (IX), 
where Y represents halogen atom such as fluorine, chlorine, bromine, iodine or esters such as sulfonyl chloride acetate, propionate, benzoate and the like or sulfonyl esters such as mesylate, tosylate, triflate and the like; P1 and P2 may be same or different and represent hydrogen, trityl, t-butyl dimethyl silyl, pivaloyl and the like or esters such as acetate, propionate, benzoate and the like or together may form methylene dioxy, isopropylidene, benzylidene, 1-phenyl ethylidene and the like; and R4 and R5 are as defined earlier,
(iii) reacting andrographolide derivative of the formula (IX) with a suitable nucleophile to produce compound of formula (X).
The protection of a compound of formula (VII) may be carried out using trityl chloride, t-butyldimethylsilyl chloride, pivaloyl chloride, dimethylsulfoxide, acetone, 2,2-dimethoxy propane, trimethyl ortho acetate, benzaldehyde, p-methoxy benzaldehyde, acetophenone and the like. The reaction may be carried out in the presence of a suitable catalyst such as SOCl2, H2SO4, HClO4, pyridinium p-toluene sulphonate, pyridine, p-toluene sulfonic acid, dimethyl aminopyridine, and the like. The reaction may be carried out in the absence or presence of suitable solvent such as benzene, DMF, dimethylsulfoxide (DMSO), acetonitrile, dichloromethane (DCM), and the like or mixtures thereof. The reaction may be carried out at a temperature in the range of 0xc2x0 C. to 60xc2x0 C., preferably at a temperature in the range of 20xc2x0 C. to 40xc2x0 C. The reaction time may range from 2 to 6 h, preferably from 2 to 4 h.
The conversion of compound of formula (VIII) to compound of formula (IX) may be carried out using halogenating agents such as thionyl chloride, thionyl bromide, phosphonyl chloride, PCl5, PBr3, bromine trifluoride, N-bromosuccinimide-hydrogen fluoride (NBS-HF), cobalt (III) fluoride, lithium fluoride, potassium fluoride, sodium fluoride, cesium fluoride, potassium iodide, sodiumiodide, iodine, iodine cerium (IV) ammonium nitrate, or R-L where R is acetyl, propionyl, benzoyl, mesyl, tosyl, triflyl and the like and L is as defined above. The reaction may be carried out in the presence of solvents such as ether, dichloromethane, chloroform, DMF, DMSO and the like; The reaction may be carried out in the range of xe2x88x9240xc2x0 C. to 160xc2x0 C. The duration of the reaction may range from 1 to 6 h.
The reaction of compound of formula (IX) with nucleophiles such as aniline, benzylamine, arylthio, piperazine, morpholine, imidazole, aminotetrazole, triazole, ester of xcex1-aminoacids, esters of xcex2-amino acids, acetic acid, thioacetic acid, alkyl magnesium halide, aryl magnesium halide, methanol, ethanol, propanol and the like may be carried out in the presence of solvents such as ether, DCM, DMF, and the like. The reaction may be carried out in the absence or presence of alumina. The reaction temperature may range from 80xc2x0 C. to 100xc2x0 C. and the reaction time may range from 1-10 h.
In still another embodiment of the present invention, there is provided a novel intermediate of formula (XI) 
where R1 represents hydrogen, halogen, thio, or substituted or unsubstituted alkyl, alkylthio, heteroarylthio, acylthio, aralkylthio, arylthio, alkylseleno, acylseleno, aralkylseleno, arylseleno, NRaRb where Ra and Rb may be same or different and independently represent hydrogen, or substituted or unsubstituted alkyl, aryl, acyl, aralkyl, heteroaryl, haloalkyl, or haloacyl or Ra and Rb together with the nitrogen atom to which they are attached may form substituted or unsubstituted 5 or 6 membered cyclic ring system containing carbon atoms, at least one nitrogen atom and optionally one or more hetero atoms selected from oxygen, sulfur or nitrogen, the cyclic ring system may contain one or two double bonds or it may be aromatic or R1 may represent OR6 where R6 represents hydrogen or substituted or unsubstituted groups selected from alkyl, aryl, aralkyl, alkenoyl, alkanoyl, aroyl, heteroaroyl, aralkenoyl, aralkanoyl, sulfonyl groups or a group xe2x80x94(CO)xe2x80x94NHxe2x80x94R7 where R7 represents substituted or unsubstituted groups selected from alkyl, aryl, or aralkyl; R4 and R5 together represents xe2x95x90CH2 or an epoxide group, their stereoisomers, their polymorphs, their pharmaceutically acceptable salts and their pharmaceutically acceptable solvates.
The present invention also provides a process for the preparation of novel intermediate of formula (XI), their stereoisomers, their polymorphs, their pharmaceutically acceptable salts or their pharmaceutically acceptable solvates, which comprises:
(i) protecting andrographolide derivative of the formula (VII), 
where R4 and R5 are as defined earlier, to produce a compound of formula (VIII), 
where P1 and P2 may be same or different and represent hydrogen, trityl, t-butyl dimethyl silyl, pivaloyl and the like or esters such as acetate, propionate, benzoate and the like or together may form methylene dioxy, isopropylidene, benzylidene, 1-phenyl ethylidene and the like; and R4 and R5 are as defined earlier,
(ii) converting the compound of formula (VIII) to a compound of formula (IX), 
where Y represents halogen atom such as fluorine, chlorine, bromine, iodine or esters such as sulfonyl chloride, acetate, propionate, benzoate and the like or sulfonyl esters such as mesylate, tosylate, triflate and the like; P1 and P2 may be same or different and represent hydrogen, trityl, t-butyl dimethyl silyl, pivaloyl and the like or esters such as acetate, propionate, benzoate and the like or together may form methylene dioxy, isopropylidene, benzylidene, 1-phenyl ethylidene and the like; R4 and R5 are as defined earlier,
(iii) reacting andrographolide of the formula (IX) with a suitable nucleophile to produce a compound of formula (X) 
where all symbols are as defined earlier and if desired,
(iv) deprotecting the compound of formula (X) by conventional methods to produce a compound of formula (XI), 
where all symbols are as defined earlier.
The protection of a compound of formula (VII) may be carried out using trityl chloride, t-butyldimethylsilyl chloride, pivaloyl chloride, dimethylsulfoxide, acetone, 2,2-dimethoxy propane, trimethyl ortho acetate, benzaldehyde, p-methoxy benzaldehyde, acetophenone and the like. The reaction may be carried out in the presence of a suitable catalyst such as SOCl2, H2SO4, HClO4, pyridinium p-toluene sulphonate, pyridine, p-toluene sulfonic acid, dimethyl aminopyridine, and the like. The reaction may be carried out in the absence or presence of suitable solvent such as benzene, DMF, dimethylsulfoxide (DMSO), acetonitrile, dichloromethane (DCM), and the like or mixtures thereof. The reaction may be carried out at a temperature in the range of 0xc2x0 C. to 60xc2x0 C., preferably at a temperature in the range of 20xc2x0 C. to 40xc2x0 C. The reaction time may range from 2 to 6 h, preferably from 2 to 4 h.
The conversion of compound of formula (VIII) to compound of formula (IX) may be carried out using halogenating agents such as thionyl chloride, thionyl bromide, phosphonyl chloride, PCl5, PBr3 bromine trifluoride, N-bromosuccinimide-hydrogen fluoride (NBS-HF), cobalt (III) fluoride, lithium fluoride, potassium fluoride, sodium fluoride, cesium fluoride, potassium iodide, sodiumiodide, iodine, iodine cerium (IV) ammonium nitrate, or R-L where R is acetyl, propionyl, benzoyl, mesyl, tosyl, triflyl and the like and L is as defined above. The reaction may be carried out in the presence of solvents such as ether, dichloromethane, chloroform, DM, DMSO and the like; The reaction may be carried out in the range of xe2x88x9240xc2x0 C. to 160xc2x0 C. The duration of the reaction may range from 1 to 6 h.
The reaction of compound of formula (IX) with nucleophiles such as aniline, benzylamine, arylthio, piperazine, morpholine, imidazole aminotetrazole, triazole, esters of xcex1-aminoacids, esters of xcex2-amino acids, acetic acid, thioacetic acid, alkyl magnesium halide, aryl magnesium halide, methanol, ethanol propanol and the like may be carried out in the presence of solvents such as ether, DCM, DMF, and the like. The reaction may be carried out in the absence or presence of alumina. The reaction temperature may range from 80xc2x0 C. to 100xc2x0 C. and the reaction time may range from 1-10 h.
The deprotection of a compound of formula (X) to produce a compound of formula (XI) may be carried out using deprotecting agent such as acetic acid, hydrochloric acid, formic acid, trifluoroacetic acid and the like. The reaction may be carried in the presence of suitable solvent such as water, THF, dioxane, DCM, CHCl3, methanol and the like or mixtures thereof. The reaction may be carried out at a temperature in the range of 0xc2x0 C. to 60xc2x0 C., preferably at a temperature in the range of 20xc2x0 C. to 40xc2x0 C. The reaction time may range from 2 to 6 h, preferably from 2 to 4 h.
The pharmaceutically acceptable salts are prepared by reacting the compounds of formula (I), formula (IX), formula (X), or formula (XI) wherever applicable with 1 to 4 equivalents of a base such as sodium hydroxide, sodium methoxide, sodium hydride, potassium t-butoxide, calcium hydroxide, magnesium hydroxide and the like, in solvents like ether, THF, methanol, t-butanol, dioxane, isopropanol, ethanol etc. Mixture of solvents may be used. Organic bases like lysine, arginine, diethanolamine, choline, tromethamine, guanidine and their derivatives etc. may also be used. Alternatively, acid addition salts wherever applicable are prepared by treatment with acids such as hydrochloric acid, hydrobromic acid, nitric acid, sulfuric acid, phosphoric acid, p-toluenesulphonic acid, methanesulfonic acid, acetic acid, citric acid, maleic acid salicylic acid, hydroxynaphthoic acid, ascorbic acid, palmitic acid, succinic acid, benzoic acid, benzenesulfonic acid, tartaric acid and the like in solvents like ethyl acetate, ether, alcohols, acetone, THF, dioxane etc. Mixture of solvents may also be used.
The stereoisomers of the compounds of formula (I), formula (IX), formula (X), and formula (XI) forming part of this invention may be prepared by using reactants in their single enantiomeric form in the process wherever possible or by conducting the reaction in the presence of reagents or catalysts in their single enantiomer form or by resolving the mixture of stereoisomers by conventional methods. Some of the preferred methods include use of microbial resolution, resolving the diastereomeric salts formed with chiral acids such as mandelic acid, camphorsulfonic acid, tartaric acid, lactic acid and the like or chiral bases such as brucine, cinchona alkaloids and their derivatives and the like.
Various polymorphs of compound of general formula (I), formula (IX), formula (X), and formula (XI), forming part of this invention may be prepared by crystallization of compound of formula (I), formula (IX), formula (X), or formula (XI), under different conditions. For example, using different solvents commonly used or their mixtures for recrystallization; crystallizations at different temperatures; various modes of cooling, ranging from very fast to very slow cooling during crystallizations. Polymorphs may also be obtained by heating or melting the compound followed by gradual or slow cooling. The presence of polymorphs may be determined by solid probe NMR spectroscopy, IR spectroscopy, differential scanning calorimetry, powder X-ray data or such other techniques.
Pharmaceutically acceptable solvates of compounds of formula (I), formula (IX), formula (X), or formula (XI) forming part of this invention may be prepared by conventional methods such as dissolving the compounds of formula (I), formula (IX), formula (X) or formula (XI) in solvents such as water, methanol, ethanol etc., preferably water and recrystallizing by using different crystallization techniques.
The present invention also envisages pharmaceutical compositions containing compounds of the formulae (I), (IX), (X), (XI), their stereoisomers, their polymorphs, their pharmaceutically acceptable salts, or their pharmaceutically acceptable solvates or their mixtures in combination with the usual pharmaceutically employed carriers, solvents, diluents and other media normally employed in preparing such compositions.
The pharmaceutical composition may be in the forms normally employed, such as tablets, capsules, powders, syrups, solutions, suspensions and the like, may contain flavourants, sweeteners etc. in suitable solid or liquid carriers or diluents, or in suitable sterile media to form injectable solutions or suspensions. Such compositions typically contain from 1 to 25%, preferably 1 to 15% by weight of active compound, the remainder of the composition being pharmaceutically acceptable carriers, diluents or solvents.
A compound of the formula (I), formula (IX), formula (X), and formula (XI) as defined above are clinically administered to mammals, including man, via either oral or parenteral routes. Administration by the oral route is preferred, being more convenient and avoiding the possible pain and irritation of injection. However, in circumstances where the patient cannot swallow the medication or absorption following oral administration is impaired, as by disease or other abnormality, it is essential that the drug be administered parenterally. By either route, the dosage is in the range of about 0.01 to about 100 mg/kg body weight of the subject per day or preferably about 0.01 to about 30 mg/kg body weight per day administered singly or as a divided dose. However, the optimum dosage for the individual subject being treated will be determined by the person responsible for treatment, generally smaller doses being administered initially and thereafter increments made to determine the most suitable dosage.
Suitable pharmaceutically acceptable carriers include solid fillers or diluents and sterile aqueous or organic solutions. The active compound will be present in such pharmaceutical compositions in the amounts sufficient to provide the desired dosage in the range as described above. Thus, for oral administration, the compounds can be combined with a suitable solid or liquid carrier or diluent to form capsules, tablets, powders, syrups, solutions, suspensions and the like. The pharmaceutical compositions, may, if desired, contain additional components such as flavourants, sweeteners, excipients and the like. For parenteral administration, the compounds can be combined with sterile aqueous or organic media to form injectable solutions or suspensions. For example, solutions in sesame or peanut oil, aqueous propylene glycol and the like can be used, as well as aqueous solutions of water-soluble pharmaceutically-acceptable acid addition salts or salts with base of the compounds. The injectable solutions prepared in this manner can then be administered intravenously, intraperitoneally, subcutaneously, or intramuscularly, with intramuscular administration being preferred in humans.
The invention is explained in detail in the examples given below which are provided by way of illustration only and therefore should not be construed to limit the scope of the invention.

A mixture of andrographolide (15 g), 2,2-dimethoxypropane (20 ml) and catalytic amount of pyridinium p-toluene sulphonate (few crystals) in a solution of benzene/dimethyl suiphoxide (300 ml/40 ml) was refluxed for 30 min. After completion of the reaction (checked by TLC), the contents were cooled to room temperature and basified with excess triethylamine (10 ml) to quench the remaining catalyst. The mixture was diluted with benzene (200 ml) and washed with water (3xc3x97300 ml). The organic layer was dried over Na2SO4 and concentrated to obtain a yellow solid which on maceration with diethyl ether gave 3,19-isopropylidene andrographolide as a pale yellow product (15 g). m.p. 194.5xc2x0 C.
1H NMR (CDCl3): xcex47.0(t, 1H, H-12), 5.1(d, 1H, H-14), 4.95(s, 1H, H-17a), 4.65(s, 1H, H-17b), 4.5(m), 4.3(d, 1H), 4.0(d, 1H, H-19a), 3.5(dd, 1H, H-3), 3.2(d,1H, H-19b), 2.6(m), 1.45(s, 31H), 1.35(s, 3), 1.2(s, 3H), 1.0 (s, 3H).

3,19-Isopropylidene andrographolide (15 g) obtained in step 1 was refluxed in distilled acetic anhydride (110 ml) for 45 min. After confirming the complete formation of the product (by TLC analysis), the contents were cooled to room temperature, diluted with water (500 ml) and extracted with dichloromethane (3xc3x97200 ml). The organic layer was separated and dried over Na2SO4 and concentrated to get a brown oily material. The crude material was purified by flash column chromatography (silica gel 230-400 mesh; 250 g, eluting system light petrol: ethyl acetate=85:15) to obtain pure 14-acetyl-3,19-isopropylidene andrographolide (13 g).
1H NMR (CDCl3): xcex47.0(t, 1H , H-12), 5.9(d, 1H, H-14), 4.90(s, 1H, H-17a), 4.60(m), 4.3 (dd, 1H), 4.0(d, 1H, H-19a), 3.5(dd, 1H, H-3), 3.2(d, 1H, H-19b), 2.4(m), 2.1(s, 3H), 1.4(s, 3H), 1.3 (s, 3H), 1.2(s, 3H), 0.9(s, 3H).

14-Acetyl-3,19-isopropylidene andrographolide (13 g) obtained in step 2 was treated with 75 ml of aq. acetic acid (aceticacid:water=7:3) and the contents stirred for 10 min at room temperature till a clear solution was obtained. The contents were diluted with dichloromethane (500 ml) and washed with water (3xc3x97300 ml) followed by aq sodium bicarbonate (2xc3x97300 ml). The organic layer was separated, dried over Na2SO4 and concentrated to get crude 14-acetyl andrographolide as a pale yellow coloured solid which was purified by crystallising in ethyl acetate/light petrol (11.2 g). m.p.169xc2x0 C.
1H NMR (CDCl3): xcex47.0(t, 1H, H-12), 5.9(d, 1H, H-14), 4.90(s, 1H, H-17a), 4.60(m), 4.2(dd), 3.9(d, 1H, H-19a), 3.5(t, 1H, H-3), 3.4(d, 1H, H-19), 2.1(s, 3H), 1.2(s, 3H), 0.8(s, 3H).

A mixture of andrographolide (5 g), 1,1-dimethoxy ethyl benzene (8 g) and catalytic amount of pyridinium p-toluene sulphonate (few crystals) in a solution of benzene/dimethyl sulphoxide (100 ml/10 ml) was refluxed for 2 h. After completion of the reaction (checked by TLC), the contents were cooled to room temperature and basified with excess triethylamine to quench the remaining catalyst. The mixture was diluted with benzene (75 ml) and washed with water (3xc3x97100 ml). The organic layer was dried over Na2SO4, concentrated and the crude material was purified by flash column chromatography (120 g of silica gel 230-400 mesh, light petrol:ethyl acetate=80:20) followed by recrystallisation with hexane/dichloromethane to obtain 3,19-O-(1-phenyl ethylidene)andrographolide (2.7 g) as a colourless product. m.p. 201.3xc2x0 C.
1H NMR (CDCl3): xcex47.6-7.2(m), 6.95(t, 1H, H-12),5.0(d, 1H, H-14), 4.85(s, 1H, H-17a), 4.50(s, 1H, H-17b), 4.4(m), 4.2(dd, 1H), 4.1(d, 1H, H-19a), 3.6(dd, 1H, H-3), 3.3(d, 1H, H-19b), 2.4(m), 1.5(s, 3H), 1.4(s, 3H), 0.4(s, 3H).

3,19-O-(1-Phenylethylidene)andrographolide (2 g) obtained in step 1 was refluxed in distilled acetic anhydride (15 ml) for 30 min. After confirming the complete formation of the product (by TLC analysis), the contents were cooled to room temperature and diluted with water (100 ml) and extracted with dichloromethane (3xc3x9750 ml). The organic layer was separated, dried over Na2SO4, concentrated to get a brown oily material. The crude material was purified by flash column chromatography (silica gel 230-400, light petrol:ethylacetate=85:15) to obtain 1.8 g of the pure 14-acetyl-3,19-O-(1-phenylethylidene)andrographolide.
1H NMR (CDCl3): xcex47.6-7.2(m), 7.0(t, 1H, H-12), 5.9(d, 1H, H-14), 4.90(s, 1H, H-17a), 4.50(m) 4.30(dd), 4.1(d, 1H, H-19a), 3.6(dd, 1H, H-3), 3.3(d, 1H, H-19b), 2.4(m), 2.1(s, 3H), 1.55(s, 3H), 1.45(s, 3H), 0.5(s, 3H).

A mixture of andrographolide (5 g), freshly distilled benzaldehyde (20 ml) and a catalytic amount of zinc chloride was stirred at room temperature for 1 h. After completion of the reaction (checked by TLC), the contents were diluted with dichloromethane and washed with aqueous sodium bisulfite solution and water. The organic layer was dried over Na2SO4 and concentrated to get 5.5 g of crude 3,19-benzylidene andrographolide. m.p. 142-143xc2x0 C.
1H NMR (CDCl3: xcex47.6-7.3(m), 7.0(t, 1H, H-12), 5.8(s, 1H), 5.0(d, 1H, H-14), 4.85(s, 1H, H-17a), 4.6(s, 1H, H-17b), 4.4(m), 4.3(m), 3.7-3.5(m), 2.7-2.2(m), 1.5(s, 3H), 0.9(s, 3H).

3,19-Benzylidene andrographolide (5 g) obtained in step 1 was refluxed in distilled acetic anhydride (15 ml) for 10 min. After confirming the complete formation of the product (by TLC analysis), the contents were cooled to room temperature and diluted with water (100 ml) and extracted with dichloromethane (3xc3x9750 ml). The organic layer was separated and dried over Na2SO4, concentrated to get a brown oily material. The crude material was purified by flash column chromatography (silica gel 230-400 mesh, eluting with light petrol:ethylacetate 90:10) to obtain 1.7 g of the pure 14-acetyl-3,19-benzylidene andrographolide.
1H NMR (CDCl3): xcex47.6-7.2(m), 7.0(t, 1H, H-12), 5.9(d, 1H, H-14), 5.8(s, 1H), 4.95(s, 1H, H-17a), 4.5(m), 4.3(d, 1H, H-19a), 3.65(dd, 1H, H-3), 3.6(d, 1H, H-19b), 2.4(m), 2.1(s, 3H), 1.5(s, 3H), 0.9(s, 3H).

Andrographolide (500 mg) was dissolved in chloroform (50 ml with few drops of methanol) and to it was added meta chloro perbenzoic acid (980 mg) and the mixture stirred for 4 h. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was concentrated and chromatographed over a colurnn of silica gel (60-120 mesh; 50 g) with chloroform:acetone (75:25) as solvent system to obtain 8,17-epoxy andrographolide as a colourless product (300 mg, 57%). m.p. 170xc2x0 C.
1H NMR (CDCl3+DMSO): xcex46.85(1H, t, J=10 Hz, C-12 H), 5.00 (1H, d, J=5.8 Hz, C-14 H), 4.40-4.00(m), 3.40(1H, t, C-3H), 3.25(1H, d, C-19 Hb), 2.75(2H, dd, J=12.4 Hz, C-17).

8,17-Epoxy andrographolide (2 g) was taken in a mixture of 2,2-dimethoxy propane (15 ml) and DMSO (2 ml). The mixture was heated to about 45xc2x0 C. until a clear solution was obtained. Then the solution was cooled to room temperature, a catalytic amount of pyridinium p-toluene sulphonate (PPTS) was added and the contents were stirred for one hour at room temperature. After the reaction was complete, the reaction mixture was quenched with triethylamine (2 ml), poured into water (100 ml), extracted with DCM (3xc3x97200 ml). The organic layer was dried over sodium sulfate and concentrated to dryness. The residue was chromatographed over a column of silica gel with chloroform:acetone (95:5) as the eluent to obtain 8,17-epoxy-3,19-isopropylidene andrographolide (2 g, 90%). m.p. 179xc2x0 C.
1H NMR (CDCl3): xcex46.8(1H, m, C-12), 5.0(1H, d, C-14), 4.4-4.0(m), 3.95(1H, d, C-19Ha), 3.55 (1H, dd, C-33), 3.2(1H, d, C-19 Hb), 2.8(2H, dd, J=12, 4 Hz, C-17 H), 1.4 (3H, s), 1.35(3H, s).
8,17-Epoxy-3,19-isopropylidene andrographolide (15 g) obtained in step 2 was refluxed in distilled acetic anhydride (110 ml) for 45 min. After confirming the complete formation of the product (by TLC analysis), the contents were cooled to room temperature and diluted with water (500 ml) and extracted with dichloromethane (3xc3x97200 ml). The organic layer was separated and dried over Na2SO4 and concentrated to get a brown oily material. The crude material was purified by flash column chromatography (silica gel 230-400 mesh; 250 g, eluting system light petrol:ethyl acetate=85:15) to obtain pure 14-acetyl-8,17-epoxy-3,19-isopropylidene andrographolide (13 g).
14-Acetyl-8,17-epoxy-3,19-isopropylidene andrographolide (13 g) obtained in step 3 was treated with 75 ml of aq acetic acid (acetic acid:water 7:3) and the contents stirred for 10 min at room temperature till a clear solution was obtained. The contents were diluted with dichloromethane (500 ml) and washed with water (3xc3x97300 ml) followed by aq sodium bicarbonate (2xc3x97300 ml ). The organic layer was separated, dried over Na2SO4 and concentrated to get crude 14-acetyl-8,17-epoxy andrographolide as a pale yellow coloured solid which was purified by crystalising in ethyl acetate/light petrol (11.2 g). m.p. 117xc2x0 C.
1H NMR (CDCl3): xcex47.1(t, H, -12), 5.9(d, H, H-14), 4.5(m), 4.25(d), 4.15(d, 1H, H-19a), 3.5(dd, 1H, H-3), 3.35(d, 1H, H-19b), 2.6(d, 1H, H-17a), 2.5(d, 1H, H-17b), 2.1(s, 3H), 1.2(s, 3H), 0.8(s, 3H).

8,17-Epoxy andrographolide (100 mg) obtained in preparation 4 above was taken in 2 ml of acetic anhydride and refluxed for 5 min. The reaction was monitored by TLC. After completion of the reaction, the reaction mixture was diluted with solvent ether, washed with water, dried over Na2SO4 and concentrated. The residue obtained was chromatographed over a column of silica gel (60-120 mesh) with light petrol:ethyl acetate (65:35) as the solvent system to afford the title compound as a colourless solid (90 mg, 67%). m.p. 195xc2x0 C.
1H NMR: xcex47.09(1H, t, J=10 Hz, C-12 H), 5.88(1H, d, J=5.8 Hz, C-14 H), 4.55(1H, C-3H), 4.5(1H, C-15Ha), 4.29(1H, C-19Ha), 4.21(1H, C-15 Hb), 4.16(1H, C-19Hb), 2.6(2H, dd, J=12.4 Hz, C-17H), 2.11(3H, S, OAc), 2.05(6H, s, OAc).